World time indicating device



H. A. LEATART WORLD TIME INDICATING DEVICE Aug. 15, 1939.

Filed May 17, 1937' Patented Aug. 15, 1939 UNITED STATES PATENT OFFlCE13 Claims.

This invention is a clock device for indicating, at a glance, thecorrect time in all of the twentyfour, standard time zones of the world.7

An object of the invention is to correctly show the hour and minute timeat all of thestandard time zones and to show the week-day of the time atthe Various zones indicated on the instrument; that is, whether the zoneis of the same day, or the day ahead or following that of the local zoneatwhich the indicator is in timed use. A further object is to provide anindicator or clock of this type that is highly reliable, is automaticwhen'used in combination with a correct, clock train, is extremelysimple in construction and mechanical operation, is springless anddevoid of fragile parts, and importantly, is based on a diurnal,conventional, twelve-hour clock-face dial so that it shows standard hourtime in the customary manner and avoids the use of any specialized clockhour dial contrivance. Additionally, an object is to provide a device ofthis class which may be readily attached to the hourhand shaft of aclock work for motivation and includes a conventionally calibrated hourface to be substituted for the usual face or dial for structural reasonsstated hereinbelow. Also, an object is to provide a universal, standardtime indicator which maybe readily operated by hand or other agent apartfrom a clock, as may be for instructional, demonstrative, experimentalor other purpose.

The invention consists of certain advancements in this art as set forthin the ensuing disclosure and having, with the above, additional objectsand advantages as hereinafter developed, and whose construction,combination, and details of means, and the manner of operation will bemade manifest in the description of the annexed illustrative apparatusor embodiment; it being understood that modifications, variations andadaptations may be resorted to within the cope, principle and spirit ofthe invention as it is more directly claimed in the appendage,

Figure l is a broken-away, facial plan of the instrument.

Figure 2 is a section on line 2-2 of Fig. 1.

Figure 3 is a facial plan of a day-wheel of the instrument,

A dial which may be of any suitable shape is here shown in the form of aflat annulus 2 with the conventional hours numbers 1 to 12 inclusive,subdivided by the usual minute marks 3 in a ring or circle 4.

Coplanar with the dial 2 and fitted turnably and concentrically in theopening, of the annulus of which the dial is formed, is a substantialzone disc 5 which is radially lined off into twelve equal sectors 6; thedisc preferably being of less diameter than theminute circle 4 so thatthe latter will show around the rim of the disc 5.

Near the outer edge of each sector 6 there is a medially disposedtubular, bearing rivet l on whichthere is turnably mounted a respective,week-day wheel 8 lying close to the back of the disc 5 and each of whichwheels 8 has an identical, indicating face divided into fourteen equalsectors 9, Fig. 3; these all being disposed upward toward their carryingdisc 5.

Radially outward from the bearings l of theseveral wheels Beachrespective sector 5 is provided with'a window opening it) through whichthe index face of the subjacent wheel 8 will be visible to the angularextent of two, contiguous sectors 9. These sectors are characterized byweek-day abbreviations as clearly shown in Fig. 3. Each sector 9represents a half-day and two adjacent sectors 9 are paired and markedwith suitable signs for the names of days of the week and sodistinguished as to show whether the half-day is before or pastmeridian. Thus, one pair of sectors shows light letters M0 for Monday,a. m. and the'next sector 9, to the right, has M0 in heavy letters, forp. In. time; the remaining days of the week being likewise contrasted.by abbreviations, in clock-wise order around the day wheel 8,

Each wheel 8 is provided with fourteen rim teeth I l pitched medially oneach related pair of day-sign sectors 9 and these teeth move in an orbitas to the center bearing l2 of the time zone disc 5 so that as the discis turned by clock train or otherwise, the outermost tooth of each wheel8 will engage every twelve hours with a fixed, but adjustable finger l3provided on the back of the hour dial or ring 2. The finger i3 isarranged just to the left of the hour numeral 12. The result of suchengagement is to turn each wheel 8 twice each day to change the day-signfrom a. in. (light) reading to p. in. (dark) reading and from p. m. toa. m.

The wheels 8 are frictionally held stationary against the back of andare carried by rotative, zone disc 5, and turn only one fourteenth of arevolution twice a day and only at the moment of engaging the fixedfinger l3.

Each sector 6 of the disc 5 is provided with a pair of the name indexesof any suitable place in, or the customary name, of the international,time system subdivision. As here illustrated, each disc sector 6 isprovided with two names l5-l6 of places which are twelve hours apart inactual time, These place or zone names are arranged in respective halvesof their sectors 6, and are shown as on opposite sides of the Wheelbearings l. The zone names are in contraclockwise order, and the zonedisc 5 is always turned clockwise, This is accomplished by providing abearing l2 which may be readily slipped onto a given, clock hour shaftafter the usual hour-hand has been removed.

To facilitate hour indication of the zone part 5 as to the hour ring 2an hour-hand or pointer I8 is turnably mounted on the disc bearing l2 sothat the hand may be rotated to any desired time zone 6 of the runningdisc 5 and in actual operation of the present indicator the hand I8 isset at the name zone of the place where the related clock is in correcttime use. The outer end of the hand 18 changeably interlocks as by ahook I9, Fig. 2, with the desired zone rivet 1, or in other suitable ordesired manner, and is thus held in place to turn with the running disc5.

In adapting the device to a standard (international) time clock theusual face and hour hand thereof are removed and the hour dial (ring) 2substituted and the zone disc 5 replaces the hour hand. Disc 5 and theday-wheels 8 are then adjusted to correctly show the hour and weekdayand its meridian period for the entire standard time system. The hourhand I8 is set correctly and is interhooked into the zone rivet 'l ofthe zone sector 6 having the place name of the locality in which theclock is situated; unless otherwise for some particular purpose.Thereafter the device will automatically operate to correctly showinternational time, at any hour, at all of the zones indicated on thename indicating the disc 5. The circumferential position of the mediallydisposed day-wheel in each zone may be used for fractional reading ofhours by reference to the nearest of the minute divisions 3; since eachdivision represents a time period of twelve minutes.

As an example, the drawing, Fig. 1, indicates by the hour hand l8 thatthe clock is being used in the Moscow-Papeete time zone. It is Tues,10:30 a. m. in Moscow and Monday, 10:30 p.,m. in Papeete. Also, the disc5 shows that it is Tues., 12:30 a. m. Pacific time and Tues, 12:30 p. m.in Khiva, Russia. In Juneau, Alaska, it is Mon., 11:30 p. m. and inBagdad it is Tues, 11:30 a. In.

As disc 5 revolves by clock power the day- Wheel 8 in the Juneau-Bagdadzone approaches the 12 clock dial mark and just before reaching thishour the center (top) wheel tooth ll engages stop finger l3 and thewheel 8 is turned one-fourteenth of a revolution on its bearing 7, andas the zone or sector 9 passes"12 oclock the time at Juneau is changedto Tues., a. m. and that at Bagdad to Tues, p. m. In the same manner,when the Pacific-Khiva zone again reaches the 12 hour mark its day-wheelis stepped over one sector 9, by the stop l3, and Pacific time becomesTues, p. m., and Khiva is Wed., a. m.

Thus, as each disc, time zone 6 reaches the stationary stop !3 thecontiguous day-wheel is set automatically to indicate the a. m. or thep. In. phase or period of the day it is entering. Each day-wheel 8 isset twice in twenty-four hours as it moves to the 12 hour sign.

An important feature of the device is disclosed as follows: Thedifference in time, for example, between Los Angeles, California, andManila, P. I., is sixteen hours. The only time that the Los Angeles dayand the Manila day is the same is between 12:01 a. m. and 8 a. m.Pacific time. At all other time Manila is a day ahead of Los Angeles andin computing time between places that is an important factor. The onlytime when it is the same week-day all over the world is from 11:00 p. m.to 12 midnight in the Fiji Islands zone, and during that hour it is thesame day all over the world. But from 12 midnight to 11:00 p. m. FijiIslands time it is always yesterday or tomorrow in some other placezones compared to Pacific time. This time relation is clearly indicatedby and is a distinctive feature of the function of the presentinvention.

This indicator can beused in any one of the twenty-four, internationaltime zones of the world as it gives the exact relation of any one isused to indicate the hour of the local, clock zone and the eificiency ofthe driving clock, to which the disc bearing i2 is attached, to showlocal time is in nowise impaired. It is understood that the hour bearingl2 may be considered as a part of a driving clock train for motivatingthe instrument. I

In the following claims the expressions meridian phase, meridian phaseindicator, a. m. and p. m. phase are to be understood in their usualmeaning with reference to time before noon or time after noon, on anygiven day.

What is claimed is:

1. A world time indicator having relatively movable parts one of whichis provided with a normal, twelve-hour clock index and the other partwith an equal number of sectors having world time place names, allconstantly visible, each sector having two place names of time zoneswhich are diametrically opposite, the place names being arranged insequence in two series in respect to their relative time zones and soarranged as to be all at one time registered with opposite hours of theclock index to show clock time at the named zone places, and constantly"visible means to show week day name and meridian phase of the time withrespect to the place names juxtaposed with each hour of the clock index;whereby to indicate at a glance at the indicator the actual meridiantime and the ing of diametrically opposite time zones, the

names being arranged in respective series in the order of their timerelation and each pair of names having respective means to show daynames and the a. m. and p. In. phase thereat, the twelve pairs of placenames concurrently reg-' istering with respect to opposite hour indicesof the index part; whereby to show at a glance at any time the week dayand the meridian phase of all time zones shown on the indicator.

3. A world time indicator having a normal twelve hour dial and arelatively turnable, concentric part having a corresponding number ofsectors each of which is provided with a pair of constantly visibleplace names of diametrically opposite world time zones; all of thesectors being registerable with the several hour divisions of the dialso as to indicate at a glance, at any relative position of the name partas to the dial,

Ill!

the relative time of all of the said time zones named, and each sectorhaving a week day and a meridian phase indicator, and a device forsuccessively turning the indicators at a given dial place.

4. A time indicator having a dial with twelve hour divisions withrelative numerical symbols, a concentric disc turnable as to the dialand having twelve time zone sections each having the names of two placesin diametrically opposite world-time zones arranged in given order intwo respective series and spaced so that all of the sections may beregistered at one setting as to the hour dial symbols to show at aglance, at the indicator, the hour at all of the time zone places namedon the disc, indicators movably mounted on the said sections and havingweek day names and meridian phases, and means to successively turn theindicators to change from phase to phase and day names in order.

5. A world time indicator having a normal twelve hour dial, a discconcentrically and turnably mounted as to the dial and having a numberof sectors equal in number to the hour divisions of the dial and saidsectors each having two world-time zone place names of diametricallyopposite time zones so arranged as to all be at one period registeredwith opposite hours of the dial to show relative time at the name zoneplaces, and each of said sectors having a window opening and a wheelshowing through each of said openings and having weekday signs and eachday being differentiated to show a. m. or p. m. phases.

6. A World time indicator having a normal, minute-divided, twelve hourdial, a part concentrically mounted as to the dial and rotative relativethereto and having a number of sectors equal to the number of hourdivisions of the dial and each sector having two names, of places intime zones twelve hours apart, which names are constantly visible andthe pairs of names so arranged as to all be at one period registeredwith opposite hours of the dial, and each place sector having meansprovided with indexes to show the days of the week at the relative, timezone, place names thereof.

7. An indicator as set forth in claim 6, and in which the day indexmeans is characterized to show before or past meridian.

8. A time indicator including a normal twelve hour dial and aconcentric, rotary disc zone into a number of place naming sectorscoordinate to and registerable with opposite hour divisions of the dialto show at a glance at any setting of the disc the time at the zoneplaces named, an actuator element fixed to the dial, and means at eachsector showing day names and meridian phases of each day for each of thenamed places and being successively actuated by, and as the disc isturned past, said element of the dial.

9. An indicator as set forth in claim 8, and including an hour-handmovably attached to the disc and turnable therewith.

10. An indicator as set forth in claim 8, and in which said meansincludes an indexed ratchet wheel rotatively mounted in each sector.

11. A world time clock having a twelve hour index, and a relativelyrotative disc divided into twelve sectors to concurrently register withthe twelve hour divisions of the index, each sector having the placenames of two diametrically opposite time zones, and each sector having aclay indemota-table wheel dividedinto sections indexed to show a. m. andp. m. phases of each day of the week in order around the wheel; and eachsector having a window opening through which only two of said sectionsof its wheel may show at one time, and means to periodically turn eachwheel one phase during the rotation of said disc.

12. In a world time clock, an index member divided into twelve equalsectors each having the place name of two diametrically opposite,international time zones, the names being arranged in pairs in a commoncircle, a radial line between the place names in each sector, and a. m.and p. In. phase, day wheels centered on the place name radii.

13. A world time clock including a part indexed into twelve hourdivisions, a relatively movable part provided with time zone place namesin time zone order and all concurrently registerable with the twelvehour divisions to show the time at all of the places named, and means toshow both the week day and the meridian phase at all of the places atany period; the hour, day and phase being observable at a glance withoutcalculation.

HOWARD A. LEATART.

ilu

